Detection of Electrochemical Reaction Products from the Sodium–Oxygen Cell with Solid-State 23Na NMR Spectroscopy

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• 作者：Zoë E. M. Reeve ; Christopher J. Franko ; Kristopher J. Harris ; Hossein Yadegari ; Xueliang Sun ; Gillian R. Goward
• 刊名：Journal of the American Chemical Society
• 出版年：2017
• 出版时间：January 18, 2017
• 年：2017
• 卷：139
• 期：2
• 页码：595-598
• 全文大小：309K
• ISSN：1520-5126

文摘

²³Na MAS NMR spectra of sodium–oxygen (Na–Ob>2b>) cathodes reveals a combination of degradation species: newly observed sodium fluoride (NaF) and the expected sodium carbonate (Nab>2b>COb>3b>), as well as the desired reaction product sodium peroxide (Nab>2b>Ob>2b>). The initial reaction product, sodium superoxide (NaOb>2b>), is not present in a measurable quantity in the ²³Na NMR spectra of the cycled electrodes. The reactivity of solid NaOb>2b> is probed further, and NaF is found to be formed through a reaction between the electrochemically generated NaOb>2b> and the electrode binder, polyvinylidene fluoride (PVDF). The instability of cell components in the presence of desired electrochemical reaction products is clearly problematic and bears further investigation.